San Carlos Park is a census-designated place (CDP) in Lee County, Florida, United States. The population was 18,563 at the 2020 census. It is allowance of the Cape Coral-Fort Myers, Florida Metropolitan Statistical Area.

San Carlos Park is located in south-central Lee County at 26°28′28″N 81°48′56″W / 26.47444°N 81.81556°W / 26.47444; -81.81556 (26.474458, -81.815467). It is an unincorporated community, bordered to the south by the village of Estero and to the east by the Three Oaks CDP. U.S. Route 41 forms the western edge of San Carlos Park, leading north 13 miles (21 km) to Fort Myers, the county seat, and south through Estero and Bonita Springs 22 miles (35 km) to Naples.

According to the United States Census Bureau, the San Carlos Park CDP has a total Place of 5.0 square miles (12.9 km), of which 4.7 square miles (12.2 km²) are house and 0.2 square miles (0.6 km), or 4.93%, are water. The land in the CDP drains west via Mullock Creek to Estero Bay, an estuary related to the Gulf of Mexico.

At the 2000 census there were 16,317 people, 5,901 households, and 4,449 families in the CDP. The population density was 3,360.5 inhabitants per square mile (1,297.5/km). There were 6,580 housing units at an average density of 1,355.2 per square mile (523.2/km²). The racial makup of the CDP was 93.84% White, 1.26% African American, 0.34% Native American, 0.70% Asian, 0.01% Pacific Islander, 2.31% from further races, and 1.54% from two or more races. Hispanic or Latino of any race were 8.14%.